BACKGROUND:: Patients who have undergone cardiac surgery, especially those with greater comorbidities, may be cared for by family members or paid aides. OBJECTIVE:: The purpose of this study was to evaluate the association between having a caregiver among patients who underwent cardiac surgery and clinical outcomes at 1 year. We hypothesized that patients with a caregiver would have longer lengths of stay and higher rehospitalization or death rates 1 year after surgery. METHODS:: We studied 665 patients consecutively admitted for cardiac surgery as part of the Family Cardiac Caregiver Investigation To Evaluate Outcomes sponsored by the National Heart, Lung, and Blood Institute. The participants (mean age, 65 years; women, 35%; racial/ethnic minorities, 21%) completed an interviewer-assisted questionnaire to determine caregiver status. Outcomes were documented by a hospital-based information system; demographics/comorbidities, by electronic records. Associations between having a caregiver and outcomes were evaluated by logistic regression, adjusted for demographic and comorbid conditions. RESULTS:: At baseline, 28% of the patients (n = 183) had a caregiver (8%, paid; 20%, informal only). Having a caregiver was associated with longer (>7 days) postoperative length of stay in univariate analysis among the patients with paid (odds ratio [OR], 3.00; 95% confidence interval [CI], 1.57-5.74) or informal (OR, 1.55; 95% CI, 1.04-2.31) caregivers versus none; the association remained significant for the patients with paid (OR, 2.13; 95% CI, 1.00-4.55) but not with informal (OR, 1.12; 95% CI, 0.70-1.80) caregivers after adjustment. Having a paid caregiver was significantly associated with rehospitalization/death at 1 year in univariate analysis (OR, 2.09; 95% CI, 1.18-3.69); having an informal caregiver was not (OR, 1.39; 95% CI, 0.94-2.06). Increased odds of rehospitalization/death associated with having a paid caregiver attenuated after adjustment (OR, 1.39; 95% CI, 0.74-2.62). CONCLUSIONS:: The patients who underwent cardiac surgery who had a paid caregiver had a significantly longer length of stay independent of comorbidity. The increased risk of rehospitalization/death associated with having a paid caregiver was explained by demographics and comorbidity. These data suggest that caregiver status assessment may be a simple method to identify cardiac surgery patients at increased risk for adverse clinical outcomes.